pragma solidity ^0.4.16;

interface ERC20 {
    
 function totalSupply() public constant returns (uint);
 function balanceOf(address tokenOwner) public constant returns (uint balance);
 function allowance(address tokenOwner, address spender) public constant returns (uint remaining);
 function transfer(address to, uint tokens) public returns (bool success);
 function approve(address spender, uint tokens) public returns (bool success);
 function transferFrom(address from, address to, uint tokens) public returns (bool success);
 event Transfer(address indexed from, address indexed to, uint tokens);
 event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
 }